books.google.ca - With many frog populations declining or disappearing and developmental malformations and disease afflicting others, scientists, conservationists, and concerned citizens need up-to-date, accurate information. Frogs of the United States and Canada is a comprehensive resource for those trying to protect...https://books.google.ca/books/about/Frogs_of_the_United_States_and_Canada_2.html?id=PH3graQZvOUC&utm_source=gb-gplus-shareFrogs of the United States and Canada, 2-vol. set